Fix - Refresh Session not working for multiple cookies (#1209) (#1227)

* Fix - Refresh Session not working for multiple cookies (#1209)

* added comments for flattenheaders fix

Co-authored-by: Joel Speed <Joel.speed@hotmail.co.uk>

* Updated Changelog.md

Co-authored-by: Rishi Kambil <rishi.kambil@lntinfotech.com>
Co-authored-by: Joel Speed <Joel.speed@hotmail.co.uk>